Former Symbionese Liberation Army fugitive Sara Jane Olson pleaded guilty Wednesday to possessing bombs with intent to murder policemen during the violent era of the 1970s revolutionary group.

Olson - a 1965 Palmdale High School graduate and pep club member who was known as Kathleen Soliah - immediately asserted outside court that she was innocent and only pleaded guilty because of the Sept. 11 terrorist attacks on New York City and the Pentagon.

``I pleaded to something of which I'm not guilty,'' she said, adding that it became clear the attacks would affect a jury and were ``going to have a negative effect on my trial.''

With law officers gaining rising esteem, Olson said, she had to consider the possibility of being convicted and sentenced to life in prison. She said her lawyers advised her that her chances of a lesser sentence would be better if she pleaded guilty.

The surprise plea came in an agreement that does not guarantee Olson a specific sentence. Her lawyers said they expected her to get about five years in prison, but the judge warned her that she could be sentenced to life behind bars.

``Are you pleading guilty freely and voluntarily?'' asked Deputy District Attorney Eleanor Hunter as she outlined the agreement in court.

``I am,'' Olson said in a strong voice during a brief hearing in open court.

Admitted attempt

She specifically admitted possessing explosive devices and attempting to explode them in two incidents - one at the Hollenbeck Police Station in Los Angeles and another near a House of Pancakes restaurant in Hollywood on Aug. 21, 1975.

In return, the prosecution dismissed three other charges.

Defense lawyers and prosecutors had spent some four hours in the judge's chambers before the agreement was announced.

Superior Court Judge Larry Paul Fidler said most of the discussions centered on the difference of opinion between the two sides over how much time Olson would have to serve in prison.

The agreement calls for Olson to surrender to the California Department of Corrections on Jan. 8 with a recommendation from prosecutors that she be allowed to serve her time in Minnesota, near her family.

Her husband, Dr. Fred Peterson, her mother, Elsie Soliah, and her daughter, Sophie Peterson, sat in the front row of the courtroom as the plea was entered. Earlier, her daughter had been in tears, hugging her mother as she entered the courtroom.

The plea ended a court case that harkened back 26 years to the era of the revolutionary SLA, which kidnapped heiress Patty Hearst. The case against Olson, 54, was resurrected with her arrest 2 1/2 years ago.

Sept. 11 effect

The plea followed many delays in bringing the case to trial, and a recent failed defense bid to put the trial off until next year because of concern that jurors might be biased because of the Sept. 11 terrorist attacks.

A grand jury had accused Olson of attempting to murder officers in retaliation for the deaths of six members of the radical group who died in a shootout and fire in 1974. The bombs did not explode.

She was indicted in 1976 under her given name, Kathleen Soliah, but remained a fugitive until her June 1999 capture in St. Paul, Minn., where she was living under the assumed name Olson.

Her arrest came soon after the FBI offered a $20,000 reward on the 25th anniversary of the SLA shootout and her case was featured on the television show ``America's Most Wanted.''

Olson vanished shortly after the attempted bombings. She maintained later that she had nothing to do with it and was not in the area when the bombs were planted. She also contended she was never a full-fledged member of the SLA, but was merely a friend of some of the revolutionaries.

Her brother, Steven Soliah, was tried and acquitted in a related 1975 bank robbery in the Sacramento area.

While a fugitive, Olson married an emergency room doctor, had three children and lived the life of a volunteer and community activist in Minnesota.

She lived in an upscale neighborhood and did not avoid public attention. Her community theater roles even drew notice from local reviewers.

The SLA, a violent group that used a seven-headed snake as its symbol, made a name for itself with the kidnapping of the then-19-year-old Hearst from her Berkeley apartment in February 1974.

Hearst soon joined the SLA and took the name Tania, and two months after her abduction was photographed holding a rifle during an SLA bank robbery in San Francisco. She was later arrested and imprisoned until President Carter commuted her sentence.

SLA member dies

In the meantime, six heavily armed members of the SLA, including its leader, an ex-convict who called himself Cinque, died in a May 17, 1974, shootout and fire that consumed a Los Angeles residence where police learned they were hiding.

Hearst later wrote a book in which she implicated Olson in SLA crimes. She had been reluctant to come to Los Angeles and testify against Olson, saying she had put the days of the SLA behind her and did not want to dredge up unhappy memories.

The prosecution said it had plans to bring up every crime committed by the SLA, including the 1973 killing of Oakland schools Superintendent Marcus Foster. Olson was not charged with that crime or any others aside from the attempted bombings, but prosecutors maintained that her association with the group showed her violent intent.

Olson - voted the Spirit and Service award by fellow Palmdale High seniors in 1965 - became politically active after seeing police beat demonstrators at the University of California, Santa Barbara, her mother said after her arrest.

After moving to Berkeley, she became friends with a future SLA member, Angela Atwood, whom she had met in the cast of a play and worked with at a Bay Area restaurant.

Olson - then still known as Kathleen Soliah - was one of the main speakers at Berkeley Park at a memorial service for the slain SLA members.

Her parents, who since their daughter's arrest have asserted her innocence, said she was never a member of the SLA. They said the surviving SLA members learned of her speech and went to her to hide them, fearing that the FBI and police intended to gun them down too.

Martin Soliah, Olson's 84-year-old father, was at home in Palmdale, when he learned of his daughter's guilty plea from a reporter.

``They didn't have any case,'' said Soliah, a retired Palmdale High School teacher and coach. ``I don't know what they worked out.''